Kevin Zeitler, Clint Boling continue to shine along Bengals' offensive line

The Bengals' offense has been among the best in football over the first quarter of the 2015 season.

While the passing attack and Andy Dalton's improvement have been the biggest focuses, the offensive line is working like business as usual. The two guys who've really impressed in recent weeks are the ones Cincinnati dedicated as much as $34 million to this offseason.

Kevin Zeitler had his fifth-year option picked up for next year, meaning he's set to make $8 million in 2016, and he's doing his best to earn it. So too is Clint Boling with the five-year, $26-million deal he got as a free agent in March. Those two have combined to allow only seven quarterback hurries and two quarterback hits in four games, per Pro Football Focus.

Boling's 7.4 PFF grade is tied for the fifth best of any guard. Zeitler has the 11th-best grade (4.2) since Week 2 after a mediocre opener in Oakland. Each of them played great in Sunday's win over the Chiefs, a game in which the Bengals rushed for 124 yards and four touchdowns. That's just a shade under Cincinnati's 128 rushing yards per game this season, the seventh most of any NFL team.

Zeitler and Boling have consistently been opening up holes for Jeremy Hill and Giovani Bernard as the Bengals have been close to unstoppable on offense.

Here, Zeitler pulls and pushes Josh Mauga five yards beyond the line of scrimmage as Hill gains three yards on 2nd-and-1.

Later in the quarter, Boling pulls and gets a great block on Ramik Wilson and drives him seven yards backward as Jeremy Hill powers for 10 yards on 2nd-and-1 in the first quarter.

Fast forward to the fourth quarter, Zeitler executes a pulling block on Pro Bowler Derrick Johnson who essentially says "uncle" as soon as he sees the big guard as Hill gains seven yards on 2nd-and-10 in the second quarter.

Johnson shouldn't feel too bad. The Bengals have been making a lot of people say "uncle" during their 4-0 start. Zeitler and Boling have been doing a lot of it, and they're earning every bit of the money Cincinnati is committing to them.